Synthesis of novel spiro pyrazolo-1, 4-dihydropiridine via one pot four component reaction
Bahman Ebrahimi Saatloo and Mehdi M Baradarani
University of Urmia, Iran
: J Pharm Sci Emerg Drugs
Abstract
Green synthesis of spiropyrazolo-1,4-hydropyridine has been reported via one pot four component reaction in EtOH/H2O (1:9) in the presence of p-TSA as catalyst. Spirooxindoles are classified as an important structural motifs due to their distribution in diverse natural products, biologically and pharmaceutical activities such as the influenza virus [1], as inhibitors of the denque virus [2] and anti-cancer agents [3]. Therefore, we conducted a series of examination the chemistry of 5,6-dihydro-4H-pyrrolo[3,2,1- ij]quinolone-1,2-dione, in which the reactivity of the ketone carbonyl group of the 2-keto-amide unit was utilized. Thus, we were able to construct various spiro[3,3’-oxindoles] via three and four component combination [4-6]. Amongst, Spiropyrazole-1,4-dihydropyridine moieties have shown important biological and medicinal activities. As a part of our ongoing interest in this context, we reported a simple and facile synthesis of a new type of spiropyrazolo-1,4-dihydropyridines (5) in the presence of p-TSA as catalyst (scheme 1) from starting materials phenyl hydrazine hydrochloride derivatives (3), 3-aminobut- 2-enenitrile (2), 3-oxo-3-phenyl propannitrile (4) and 5,6-dihydro-1H-pyrrolo[3,2,1-ij]quinolone 1,2(4H)-dione (1) in environmentally friendly solvent, EtOH/H2O. Scheme: 1 The key features confirming the structures can be illustrated with the data for product (5). The IR spectrum showed absorptions at 3207 (NH), 2190 (CN), and 1678 (C=O) cm−1. The 1H NMR spectrum exhibited a singlet for the methyl group at δ 1.50 ppm and the much more acidic NH (conjugated through the double bond to the nitrile) produced a signal at δ 10.43 ppm.In the 13C NMR spectrum of product (5) (with 25 distinct resonances) the carbonyl and nitrile carbons appeared at δ 175.01, 118.7 ppm, respectively.
Biography
Bahman Ebrahimi Saatluo received his B.Sc in Applied Chemistry (2007) from the Urmia University. He will receive his Ph.D degree in Organic Chemistry from the Urmia University (Iran) in 2018 after completing his research in the Study of Synthesis of Polyazadodecahedrone and Synthesis of Spirooxindole Compounds of 1,2,3,4- Tetrahydroqunoline by Base , Acid and Nano Catalysts under the guidance of Professor Mohammad Mehdi baradarani. His current research interest focus on the synthesis of Spirooxindole and supramolecular in heterocyclic for organic synthesis.
E-mail: ebrahimisaatlo@gmail.com
